A System Line Overload Index for Contingency Assessment of Nigeria's 330kV Transmission System

Authors

  • Ganiyu A. Ajenikoko  Department of Electronic & Electrical Engineering, LadokeAkintola University of Technology, P.M.B. 4000, Ogbomoso, Nigeria
  • Anthony  Department of Electronic & Electrical Engineering, LadokeAkintola University of Technology, P.M.B. 4000, Ogbomoso, Nigeria
  • A. Olaomi  Department of Electronic & Electrical Engineering, LadokeAkintola University of Technology, P.M.B. 4000, Ogbomoso, Nigeria

Keywords:

Contingency, SLOI, Sending End Voltage, Receiving End Voltage, Transmission System, Power Grid.

Abstract

Contingency analysis is an abnormal condition in electrical network. It puts the whole system or a part of the system under stress. It occurs due to sudden opening of a transmission line, generator tripping, sudden change in generation and sudden change in load value.

This paper presents a System Line Overload Index (SLOI) for contingency assessment of Nigeria’s 330kV transmission system. The analysis started with the determination of the receiving and sending end voltages of the buses in order to compare their values for safety operation. The ratio of the receiving and sending end voltages of the buses was determined as a basis for the mathematical computation of the System Line Outage Index (SLOI).

The results of the work showed that the outage of Osogbo to Aiyede had the most critical effect on the system because, at this line, a peak SLOI value of 0.99998 was obtained with sending and receiving end voltages of 1.84V and 1.81192V respectively. The outage of Osogbo to Ikeja West line had the least SLOI value of 0.069, hence the least critical effect on the system. This SLOI value gave a corresponding receiving and sending end voltages of 1.04272V and 1.12V respectively. Additional lines should be used to connect Osogbo to Aiyede to create more links for power to be transmitted to Lagos area so as to reduce the SLOI value of Osogbo to Aiyede line.

The work will stress the importance of operating the transmission system defensively to avoid system collapse due to overloading so as to improve the lines’ active power capability contingency event using Flexible AC Transmission (FACT) devices because of their fast switching ability.

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Published

2015-10-25

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Section

Research Articles

How to Cite

[1]
Ganiyu A. Ajenikoko, Anthony, A. Olaomi, " A System Line Overload Index for Contingency Assessment of Nigeria's 330kV Transmission System, International Journal of Scientific Research in Science and Technology(IJSRST), Online ISSN : 2395-602X, Print ISSN : 2395-6011, Volume 1, Issue 4, pp.16-22, September-October-2015.